The present invention relates to a tubular body which improves the mixed state or heat conduction efficiency of a fluid flowing therein.
It has been common practice to fabricate the heat conduction pipe of, say, a heat exchanger of a material with high heat conductivity or to provide said pipe with fins to increase the area of heat conduction, thereby improving the heat conduction effect. Such a practice has, however, been unable to produce a pipe meeting various requirements for increased efficiency of the heat exchanger.
Aimed at solution of this problem, the tubular body according to the present invention is characterized by being provided on the external surface with a series of periodically wavy recesses of specific depth and angle and accordingly on the internal surface provided with the corresponding series of similarly wavy projections.